a. Field of the Invention
The present invention relates to a method of manufacturing a granular solid catalyst useful for polymerizing olefin and like purposes.
B. Description of the Prior Art
The art of utilizing Lewis acids like aluminum chloride for polymerizing olefins has been known for a long time, but inasmuch as such conventional catalysts are soluble in olefins, they are hard to separate after termination of the reaction, and in the present circumstances, they must be removed through decomposition by the use of aqueous alkali, aqueous ammonia, adsorbent and the like. Accordingly, these catalysts are difficult to reuse and unfit for use in reactions effected by employing a fixed bed or a fluid bed.
With a view to overcoming such defects, there have been made various studies on complex catalysts consisting of aluminum chloride and polar organic compounds: for instance, Japanese Patent Publication No. 3840/1969 has disclosed the method of polymerizing olefin by the use of a catalyst prepared by dissolving excess aluminum chloride in a complex consisting of aluminum chloride and ethyl acetate at the ratio of 1:1, which renders it easy to separate the catalyst, and U.S. Pat. No. 2,697,694 has proposed a catalyst prepared by dissolving excess aluminum chloride in a complex consisting of aluminum chloride and acetone at the ratio of 1:1, said catalyst being reported to have the same effect as that in the preceding catalyst.
However, these complexes have no more than the function as a solvent to dissolve aluminum chloride, and the polymerization reaction per se is effected by virtue of the excess dissolved aluminum chloride, so that, upon completion of the reaction, the same treatment as in the case of the ordinary catalysts consisting exclusively of aluminum chloride is required. Further, in the case where these complexes are to be used repeatedly, it is necessary to effect the next reaction by replenishing the aluminum chloride consumed in the previous reaction.
Therefore, the known methods employing these complexes are no more than a method wherein a solvent to dissolve aluminum chloride is being circulated, and the catalyst not only becomes unfit for reuse as it is after it is once used, but also is inapplicable to a continuous reaction employing a fixed bed or a fluid bed.